/*
  将下面异步代码使用 Promise 的方法改进
  尽量用看上去像同步代码的方式
  setTimeout(function () {
    var a = 'hello'
    setTimeout(function () {
      var b = 'lagou'
      setTimeout(function () {
        var c = 'I ♥ U'
        console.log(a + b +c)
      }, 10)
    }, 10)
  }, 10)
*/

const changeName = name => {
  return new Promise(resolve => {
    setTimeout(function() {
      resolve(name)
    }, 10)
  })
}

changeName('hello')
.then(name => changeName(name + 'lagou'))
.then(name => changeName(name + 'I ♥ U'))
.then(console.log)